Process for making tire patches



Jan. 8, 1929.

' 1,697,955 P. E. HAWKINSON- PROCESS FOR MAKING TIRE PATCHES File?. Aug. 25, 1925 4 SheeJcs-Sheet l Jan. 8, 1929.

P. E. HAWKINSON PROCESSl FOR MAKING TIRE PATCHES Filed Aug. 25, 1925 4 Sheets-Sheet 2 X' Hl J/mm/w.

' 1,697,955 P. E. HAWKINSON PROCESS FOR MAKING TIRE PATCHES Filed Aug. 25, 1925 4 Sheets-Sheet 3 Jan. 8, 1929. 1,697,955/ P. E. HAWKINSON PROCESS FOR MAKING TIRE PATCHES Filed Aug. 25, 1925 4 sheets-Sheet 4 Patented Jan, 8, 1929.

NETE@ STATES FACTURING C0., OF MINNEAPOLIS, MINNESOTA, A CORPORATIONv OF MINNESOTA.

PROCESS FOR MAKING TIRE PATCHES.

Application led August 25, 1225. lSerial No. 52,474.

My invention relates to an improved tire patch and to a process and machine for producing the same. The patch is an improvement upon the patch set forth in my Patent No. 1,436,394, dated November 21, 1922. The process and machine are adapted for the making of the improved patch, preferably by cutting the desired' number and shape of plies or layers from the carcasses of used tires.

Inthe usual, method heretofore employed in makingpatch'es for repairing pneumatic tire casings, as set forth in my above mentioned patent, it has been the practice to strip or pull the desired number of plies or layers of fabric and interposed rubber from i thecarcass of a used tire; cut the removed layers or plies to the desired shape (usually round) and then skive the edge so that a 4neat or fiat joint may be ma de with the carcass of the tire to be repaired. When the plies `for patch material are removed from the tire carcass in this manner. the separation is usually uneven, the-interposed layer of and Vto thereb give the surfaces a uniformv exposure of fa ric. Unless the buiiing of this surplus rubber from the surfaces of the patch is ,very carefully done thefabric is apt to.

become loosened andcparts thereof removed, thus reducing its strength to some extent. The use of such fabric faced`4 patches inrepairing tires according to the method set forth in my previously mentioned patent or dinarily requires that, before the patch is placed, one or both of its fabric faces be covered or coated with a thin layer of gum rubber or similar material. These extra steps of removing the uneven layer of original rubber and then appl ing the thin and uniform coating of new rubber adds to the labor and expense of making the patches. Furthermore, this application of uncured rubber to the 'surfaces of the patch material does not always produce a thorough union between the rubber and the buifed fabric, such, for example, as exists between the layers of fabric and vulcanized rubber of a tire casing. VIt has also been found that, in pullin Athe patched material from the carcass, the abric at the plane of cleavage is oftentimes in- ]ured because of the tendency todeform and tear the fabric and to stretch and displace the strands of which it is composed.

The principal object of my present invent1on is to provide a patch having the same general type and characteristics of that disclosed in my previously-mentioned patent,

but which is covered on either or both of its surfaces with a thin and .uniform layer of the original interposing layer of vulcanized rubber; and to provide a process and a machine whereby such patches or patch material may betaken from the carcasses of used tires.

I prefer to take the patch material from used tires because the plies are firmly Welded or cemented together, all of the stretch has been removed from the fabric so that the patchk will remain in position and will not bulge, the material is formed to the shape of the tire to be repaired, and furthermore the materials ordinarily used in tire manufacture are of a better grade and quality than can be obtained upon the market merely for tire repair purposes.

Another object of my invention is to provide a-machine which is simple in construc- -ti'onvand operation and is adapted to slice rubber and other similar materials into sheets of desired thickness.

A further object is to provide a machine .which is particularly adapted to cut one or more plies of fabric from a pneumatic tire casm A. further object is to provide a machine for the above mentioned purposes, in V.which the cuttingmeans is readily removable from operative position and to provide means for automatically connecting the cutting means to the driving means-when the cutting means is moved to operative position,

A further object is to provide a novel form of cuttin means and a novel means for sup-4 porting, riving and adjusting the same.l

A further object is to provide a novel form of adjustable feeding means for feeding the tire casing to thecutting ineans. l l

A furtherk object is to provide a noveli form of tire patch; Y

Other objects will appear from the following description in which: y

Figure 1y is a ,plan view of my machine showing the parts in normal position; l

Figure 2 is a front elevation of the machine with portions cut awayto better show the operative parts Figure 3 is a left side elevation showing the cutting knife in operative position.;

Figure 4 is a vertical cross-'section taken on the plane represented by the line 4-4 in Figure 1, showing 'the cut-ting means in inoperative position;

Figure 5 is a vertical section taken on the plane represented in line 5-5 in Figure 1, showing the partsin operat-ive position.;

Figure 6 is a similar section taken on the plane represented b the line 6-6 in Figure `1, showing latching ar which holds the parts in operative position;

Figure 7 is a detailed section taken on the plane represented by the line 7-7 in Figure 1 and showing particularly the means for operating the feeding rollers;

Figure 8 is a detailed elevation of the knife guide means, partly broken away to show the roller;

, Figure 9 is a plan `view of thel knife guide` means, and f Figure 10 is a vertical section of the knife guide means taken on'the plane represented by the line A10--10 in Figure 9.

My machine is mounted on a structural frame consisting offour vertical legs 1 which Imay be secured to the floor by angle iron clips 2. Transverse cross rods 3 and longitudinal rods 4 are bolted to these legs 1. 'Crossed tie members 5 are securedy to these vertical members 1 for additional strength and rigidity. At the top of the frame transversebars 6 are secured and form the bearing sup ort lfor the knife frame supporting shaft 7, t e knife frame consisting of L-shaped arms 8 which are secured at one end to the shaft 7 by means of set screws 9. The right hand arm 8 (Figure 1) isy extended at 8a to form a handle by which theframe may be raised. The L- shaped members 8 have bearings 10 formed therein adapted to receive the shafts 11 and 11a upon which the 4pulleys'12 are secured. Collars 13 are secured by set screws torthe upper end of the shafts 11 and 11, the lower surface of these collars forming a bearing j surface for the shafts 11.

- 4) is secured to the endl of the shaft 11 and,

when the knife frame is in lowered operativa position, is adapted to engage the tenon member 15 secured t'o the upper end of a power shaft 16, rotatably held in the bearing supn the upper 20 which is clamped to the lower longitudinal l rods 4.

Bolted between the L-shaped members 8 are the rods 21 and 22 which aid in making the' knife frame rigid and also serve to hold the guide supports 23 which are clamped to these bars by means of bolts which pass through the supports, and also through similar but shorter clamping bars 24. The knife guide ,25 is bolted near its ends to the ends of the support bars 23.

The guide 25, as is best-shown in Figures 5,

8, 9, and 10, is triangular in cross-section and at its downwardly pointing apex has a full length slot 25*1 of sufficient width and depth to receive the major portion of the band' knife 14`which moves longitudinally therethrough and is guided thereby. Mounted in recesses 25b formed in the upper portion'of the guide 25 at suitable intervals, are the antifriction means which serve toy apply downward pressure to the band knife, here illustrated as ball bea-ring rollers 26.

As said before, the shaft 7 and consequently the entire knife supporting frame,

may be pivotally moved relatlve to the main frame. When in raised or inoperative position the elbows of the L-shaped members 8 engage the upper rear longitudinal rod 4 and the frame is thus held in approximately vertical position as is shown in Figure 4.' It is desirable to have the lower operative position adjustable, and to accomplish this a pair of arms 27 are securedto the rod 22 and are adapted to have their endsf'engagebolts 28,

which are vertically adjustable in the feeding means supporting bars 29 and 30 respectively. Asuitable latching lever 31, pivoted on the bar 22 and having a handle portion 3la and an open slotl 31b which is adapted to engage the rod 4`,.is provided to lock the band knife support vframe in lower operative position.

A knurled or roughened feed roller 32 is rotatably supported on a shaft 33 whichat its ends is carried by a pair of guide blocks 34 having slots34 These guide blocks are carried bythe bars 29 and 30 respectively. A pair of adjusting screws 35 are screw threaded through the blocks and have their ends rotatably secured to the ends of the shaft 33. Suitable locking' thumb nuts 36 are l. Secured at the endof the bars 29 and 30 threaded on these screws;so that the roller i -mav be securely held in adjusted position.

iso

is a-sevcond pair of guide blocks 36 to which is bolted a bar 37. Another bar38 extends through the slots 361L in the blocks 36 and at its ends is bolted to. the links 39 and 40 re-l spectively. A roller 41 having an outer surface of soft rubber or similar material which is adapted to conform to irregularities in the surface 0f the material to be cut and thus tend to equalize the distribution of the. pressure of the Aroll upon the material, is fixed to a shaft 42. the ends of which extend through the slots 36a and are journaled in the links 39 and 40 respectively. A wormwheel 43 is fixed to the righthand (Figure 1) end. of the shaft 42 and is engaged for rotation by a worm- 44 which is keyed to a shaft 45 carried in .bearings 46 attached to the link 40.l A crank handle'47 is shown yintegral with the worm shaft 45. The tire or other material being sliced is fed upwardly to the band knife by manually turning this crank. It is to be understoodl however that the feed can readily be made' automatic by connecting this shaft with the drive shaft by suitable gearing.'

, In order to gripv the tire or similar *stockv between the rollers, the .roller 41 may be moved toward the roller 32. This is accomplished by .turning the crank 48 integral with the screw 48 which is threaded through the left-hand end ortion of the bar 37 and at its end is rotatab y mounted in the bar 38, being prevented from axial movement therein by the collar 49 and the sprocket 50 which are fixed to the screw. A similar screw 51 vcarrying a similar sprocket 52 and collar 53 is similarly mounted in the -bars 37 and 38. A chain 54 connects these sprockets. It will be seen. that movement of the screw 48 lwill thus be directly communicated to the screw 51 so that the bar 38 and consequently both ends of the roller 41 willl be moved equal distances. f

i In Figure 2, guards 55 are/shown attached to the band knife frame toprotect the operator from the pulleys and knife.

To operate the machine, the roller 32 isy first adjusted to !be the exact distance from v x the cutting edge bf the band knife necessary t0 cut the desired number of plies of fabric from the tire. The blocks 34 may be suitably graduated adjacent the slots 34a and 4a vertical centerline marked on the ends ofthe shaft 33' in' order .to facilitate this adjustment. vThe end of a tire (whichhas first been transversely severed) is flattened and insertedbetween the rollers from below with the fabric side towards the roller 32. The handle 48 is then turneduntil the end of the tire is securely clamped between the rollers. The band knife frame is then brought down to operative position, and held there by means of latch lever 31. It will be remembered that when the knife is moved to operative position, a driving connection to the knife is automatically established through the mor-` knife will start moving and the tire casing may be fed upwardly by turning the crank 47. The wedge-shaped portion of the guide 25 guides the severedportions of the 4tire casing away from the knife, thus permitting the knife to levenly cut into the rubber between the yplies of fabric, reducing friction, and preventing the sides of the knife from rubbing the rubber surface from the material.

The adjustment of the rollers is sufficiently sensitive to make it possible to slice the plies of fabric from the tire casing by cutting through the rubber layer between the plies of fabric with such accuracy that no bufling is required to fit the material for use. The operation may be repeated until a. different number of plies are desired or a different type of tire casing is to be used.

The patch disclosed herein forms the subject matter of my co-pending divisional ap-l plication, Serial No. 240,353, filed December 16, 1927, and the machine. herein disclosed is shown and claimed in my co-pending application, Serial No. 240,354, filed December 16,

template such variation as may be desirable or useful in the particular adapt-ation of the invention shown, or in its adaptation to other machines. I do not restrict myself in any unessential particulars, but whatI claim and desire to secure by Letters Patent is i '1. The method of making pneumatic tire casing 'patches which consists infsevering a plurality of pliesof fabric from a used tire casing by cutting through thelayer of rubber between the plies of fabric.

2. The method of making tire patching material which consists in cutting a used pneumatic tire casing transversely and then severing plies of fabric from said caslng by lcutting through the intermediate layers of `of plies of fabric vulcanized together by intcrmediate layers of rubber, which )fabric has A layers of rubber, which consists in flatteningof fabric from the carcass by cutting through' been stretched to conform to the shape of a tiie casing,y and' severing a plurality of plies of fabric from said material by cutting through the Yintermediate layers of rubber.

'5. The process of making tire patching material from tire carcasses having plies of fabric vulcanized together '-by intermediate the tire carcass, severing a plurality of plies the intermediate layers of rubber, cutting out circular tire patches from said plies, and skiving the edges ofthe circular patches.

6. r1`he method of forming a, tire Irepair sheet from the inner .fabric body of an old tire casing, which consists in cutting through the fabric body of the tire casingy at ya uniform distance from` the inner face thereof and through yone of the layers of vulcanized rubbei' uniting the fabric plies of the casing and thereby providing the convex face of the reterial from a tire carcass composed of alternate'layers ofl fabric andv vulcahized rubber, which comprises taking from the carcass a "sheetof material of the desired number of layers by cutting through a layer of the rubber between two adjacent layers of fabric, leaving a fully exposed thin film of the original vulcanized rubber on each of the fabric layers that originally were adjacent and joined to each other by the cut layer of rubber.

In witness whereof, I hereunto subscribe my name this 20th dayof August, 1925.

PAUL E. HAWKINSONJ 

